Gas compressor

ABSTRACT

The machine has a primary gas inlet for the first of two motorpowered compressing stages with two, separate, secondary gas inlets confined within walls of the primary inlet housing. The first compressing stage has a compressor wheel with a turbine wheel integral therewith, the turbine wheel having compressed gas addressed thereto, selectively, either not at all, or by either one or both of the secondary inlets from a compressed gas discharge line for energy recovery to help drive the compressor wheel while also controlling surge and maintaining compressor operation at an optimum design level. The machine further includes means for preventing an icing-up of the first compressing stage even under below-freezing environmental conditions.

United States Patent [191 Hornschuch et a1.

11 3,826,594 1 July 30, 1974 GAS COMPRESSOR [75] Inventors: Hanns Hornschuch; Leroy M.

Krouse, both of Easton, Pa. [73] Assignee: IngersolI-Rand Company, New

York, NY. [22] Filed: Oct. 17, 1973 [21] Appl. N0.: 407,252

Related U.S. Application Data [63] Continuation of Ser. No. 159,130, July 2, 1971,

abandoned.

[52] U.S. Cl 417/245, 415/79, 415/143, 417/374, 417/409 [51] Int. Cl. F04b 3/00, FOld 13/00 [58] Field of Search 417/391, 409, 79, 323 U, 417/323 P, 384 D; 415/116, 143, 116 A, 115 v T, 115 E [56] References Cited UNITED STATES PATENTS 1,066,581 7/1913 Brown 417/323 1,110,864 9/1914 Banner 417/323 1 154,959 9/1915 Banner 417/323 1 280,276 10/1918 Morse 417/323 2,238,502 4/1941 Muir et al. 415/143 2,322,338 6/1943 Baumann 417/323 2,656,096 10/1953 Schwarz 415/116 Primary Examiner-William L. Freeh Assistant Examiner-(3. P. La Pointe Attorney, Agent, or Firm-Bernard .1. Murphy [5 7] ABSTRACT The machine has a primary gas inlet for the first of two motor-powered compressing stages with two, separate, secondary gas inlets confined within walls of the primary inlet housing. The first compressing stage has a compressor wheel with a turbine wheel integral therewith, the turbine wheel having compressed gas addressed thereto, selectively, either not at all, or by either one or both of the secondary inlets from a compressed gas discharge line for energy recovery to help drive the compressor wheel while also controlling surge and maintaining compressor operation at an optimum design level. The machine further includes means for preventing an icing-up of the first compressing stage even under below-freezing environmental conditions.

24 Claims, 7 Drawing Figures PAIENIEUM 3.826.594

saw 1 0f 5 4 J I L INVENTORS HAN/V5 HORNSCHUCH LEROY-M. KROUSE AGENT PATENTED M30374 v 3.826.594

INVENTORS HAN/v5 HORNSCHUCH LEROY M. KROUSE AGENT Pmmwww 3.826594 SHEU I; 0F 5 r INVENTORSI HAN/v5 HORNSCHUCH LEROY M. KROUSE PATENTEU M30374 SHEET 5 OF 5 I (2 STAGE) E G A T S 3 AMBIENT INLET TEMPERATURE -F (COOLER EXIT TEMPERATURE 95F) ZSTAGE VS 3STAGE; FIRST STAGE INLET TEMPERATURE FOR 20% DELIVERY FIG. 7

WHMLU ,T NGU N W 0 n mmk A 0. w HM 5y NOW MR HM GAS COMPRESSOR This is a continuation of U.S. Pat. application Ser.

'No. 159,130 filed July 2, 1971, now abandoned.

is known. However, the known gas compressors with recovery turbines, such as thatof Banners teaching, have disadvantages that, for instance, considerable dismantling and disassembly must be undertaken to effect maintenance thereof. So also, the known apparatus have. complex discharging-pressure-sensing and turbine-admission arrangements, but more importantly, the known admission arrangements for the turbines and therefrom to the compressor first stages, give rise to a flow condition which poorly meets the proper flow pattern for the first compressor stages. Prior art machines, absent extraneous heaters, lack means operative for preventing an iceup of the first stage of compression under below-freezing environmental conditions.

It is an object of this invention to avoid the disadvantages found to obtain in prior art gas compressors having recovery turbines.

It is another object of this invention to teach a gas compressor which comprises at least a first gas compressing stage with means for compressing gas admitted to said stage; a plurality of not less than three separate gas inlet means for admitting gas to said compressing means; and means in fluid communication with said first stage for discharging compressed gas therefrom; wherein said inlet means of said plurality are disposed in parallel for admitting gas tosaid first compressing means in a same common direction which complements the proper flow pattern for the first compressing stages; and at least two given inlet means of said plurality are partially confined within another inlet means of said plurality.

It is yet another object of this invention to provide a gas compressor comprising motor means; first means, powered by said motor means, for receiving gas and for compressing gas admitted thereto; and second means, powered by said motor means, operative for preventing icing of said first means from any moisture borne by g admitted to said first means.

A feature of this invention comprises a gas compressor machine which has a primary gas inlet for the first of two motor-powered compressing stages with two separate, secondary inlets confined within walls of the primary gas inlet housing. The compressing stage has a compressor wheel to which is coupled a turbine wheel, the latter having compressed gas conducted thereto, selectively, by one, or both or neither, of the secondary gas inlets for energy recovery to help drive the compressor wheel, and also for controlling surge, and to maintain the machine at an optimum design level of operation.

Further objects and features of this invention will become more apparent by reference to the following description taken in conjunction with the accompanying figures in which:

FIG. I is a side elevation view of a machine according to the invention;

FIG. 2is a front elevation of the novel machine;

FIG. 3 is a combined schematic and pictorial illustration of the machine layout and of the gas flow arrangement therefor;

FIG. 4 is an axial cross-section of the first compressing stage taken along Section 44 of FIG. 2;

FIG. 5 is an axial crosssection of the second compressing stage taken along Section 5-5 of FIG. 2;

FIG. 6 is an axial cross-section of the turbine inlet control valving taken alongSection 66 of FIG. 2; and

FIG. 7 is a chart on which is plotted, for purposes of comparison, adjusted inlet temperatures, for two-stage and three-stage compressors vs. ambient temperatures.

As shown in FIGS. 1 and 2, a gas compressor 10 has an air filter 12 in surmounting enclosure about the primary or first gas inlet 14 for a first gas compressing stage 16. The second gas compressing stage 18 of the machine has a cover 20which closes off the stage from the atmosphere, but which facilitates a maintenance access to the stage. The machine encloses an intercooler 22 for which there is an access cover 24 bolted to the side. Two demisters 26 and 26' are also confined within the machine, the same also having an access cover 28. All of the foregoing are supported within a base-and-casing 30 of the machine. Tothe rear of the casing 30 is mounted a motor 32. which provides the primary motive power for the compressor 10. A compressed gas outlet 34 opens at the top of the machine, i.e., the compressor 10.

With reference to FIGS. 3, 4, and 5 it will be seen that the novel gas compressor comprises a primary gas inlet housing 36 for the first compressor stage 16 which defines an inlet port 38. Downstream of port 38 is rotatably mounted a first stage compressing wheel 40. A passageway 42, formed within the casing 30, conducts the compressed gas product from the first stage 16 to the inter-cooler 22, from there to the first-pass demister 26, through the latter, and then through the secondpass demister 26. Thereafter, the cooled and demisted compressed gas is conducted by way of another passageway 44, formed within the casing, to the inlet housing 46 of the second compressing stage 18. The second compressing stage 18 comprises a second stage compressor wheel 48 rotatably mounted within its housing 46 from which a further passageway 50, formed within the case 30, conducts the compressed gas to a using end item 52. A gear train 56 driven by a shaft 58 which, in turn, is powered by the motor 32, rotates both compressor stage wheels 40 and 48.

According to the invention, a turbine wheel 60 is mounted integral with the wheel 40, rotatably within a pod or nacelle 62. The nacelle 62 is rigidly supported within the inlet housing 36 by means of struts 64. In the embodiment here described, there are four struts 64, but this is a matter of choice. A wall member 66 subdivides an inner nacelle chamber 68 and a pair of conduits 70 and another pair of conduits 72, formed within the struts 64, open at one end of the divided nacelle chamber 68 and on the other end on two passageways 74 and 76, respectively. (Only one conduit of each pair is shown.) Passageways 74 and 76 are formed within the machine casing 30 and are through-connected, at the opposite ends, to a three-position valve 80. In its three functional positionings, valve 80 is either fully closed, half open, or fully opened; the three positionings are effected by a movement of an actuating plunger 82 to effect a modulated recovery of the compressor output. Valve 80 has built therein sections A, B, C, and D. Section A and B interdict a flow of fluid therethrough, and sections C and D accommodate a fluid flow. With the valve 80 arranged for enabling sections A and B, the valve is fully closed. With the valve 80 arranged for sections B and C to be in operation, the valve can pass up to 50 per cent of the gas compressor output therethrough to the turbine wheel 60. This is the positioning shown in 'FIG. 3. When the valve 80 has sections C and D in operation, it can pass the remainder of the total output product of the gas compressor therethrough to the turbine wheel 60.

The air outlet 34 is shown in communication with a pressure sensing valve actuator 86 (FIG. 3). The actuator 86 has a ganged mechanical connection with the plunger 82 of the valve 80. A juncture 88 couples a bypass line 90 to passageway 50 and valve 80. Therefore, the sensing valve actuator 86 constantly monitors the back pressure in the discharge passageway 50 and in response thereto operates valve 80. When the using end item 52 is shut down, and back pressure builds up in the compressor discharge passageway 50, the valve 80 is actuated first to half, and then to a fully opened position whereby the gas product is recycled through the turbine 60. Accordingly, the compressor at all times operates within its design rating, does not surge, and the expansion of the gas at the turbine 60 effects an energy recovery which minimizes the loading of the motor 32.

When the valve 80 is but half open, as depicted in FIG. 3, as much as half of the total gas product of the compressor is conducted through by-pass line 90, section C of valve 80, passageway 74, and the pair of conduits 70 for admittance into one half of the nacelle chamber 68, and from there to the turbine wheel 60.

When the valve 80 is fully open, the remaining half of the gas product courses through line 90, section D of valve 80, passageway 76, and the pair of conduits 72 for admittance into the'other half of the nacelle chamber 68. Thus, the valve provides infinite-step control.

Passageways 74 and 76 open out of the casing 30 (as shown in FIG. 6) onto valve 80, at one end thereof, and define enveloping chambers, at the other end thereof (FIG. 4) concentric with the nacelle chamber 68. These chambered-ends of passageways 74 and 76 are formed of relieved areas in the outer periphery of the inlet housing 36. As the conduits 70 and 72 open through the walls of the housing 36, they communicate the nacelle chamber 68 with these passageways 74 and 76.

A first end of passageway 42, as shown in FIG. 4, commences in a discharge annulus concentric with the first stage compressor wheel 40. Gas compressed by the first stage 16 proceeds therefrom down through the casing 30, (the specific channeling not being shown) into the'inter-cooler 22, and then the demisters 26 and 26. The cooled, demisted gas rises from demister 26 within the casing 30 via the passageway 44 a termination thereof defining a plenum within the second stage housing 46 (FIG. 5). This gas product is addressed to the second stage compressor wheel 48, where it is further compressed, and conducted therefrom to the discharge passageway 50. As depicted in FIGS. 4 and 5, the discharge passageway 50 extends transverse of the first and second stages 16 and 18, above the respective housing 36 and 46 thereof, with the outlet 34 thereof substantially above housing 36.

Passageway 50 also extends, in the same transverse direction, to open onto valve 80, as shown in FIG. 6.

In FIG. 6, where the details of valve are presented it can be seen that plunger 82 carries a hollow cylinder 98 which has axial ports 100, and radial ports 101 formed therein by means of which the recycled gas product is by-passed from passageway 50 and conducted into passageway 74 or to both passageways 74 and 76. In the position shown in FIG. 6, the valve is completely closed and there is no recycling of the gas product. Circumferential seal 102 prohibits a communication of the gas product with passageway 74. When the sensor-actuator detects back pressure in the passageway 50, it withdraws the plunger 82; in turn, plunger 82 causes the cylinder 98 to retract (that is, move toward the right as shown in FIG. 6) and seal 102 broaches the termination of passageway 74, therefore, first a small fraction, then more, then as much as one half of the compressor product is conducted therethrough to the turbine wheel 60, as the cylinder 98 progressively uncovers passageways 74. As the back pres sure continues to rise, plunger 82 retracts the cylinder further, until circumferential seal 104 proceeds to open up the termination of passageway 76, whereupon, progressively, the remaining half of the total output of the gas compressor 10 is conducted to the turbine wheel 60 for expansion, energy recovery, and recycling. Thus, we teach an infinite-step, modulated, recovery.

The two, secondary inlets to the first compressing stage, which are defined by conduits 70 and 72, and the respective portions of nacelle chamber 68 are paralleled and in-line with the primary inlet defined by the annular inlet chamber about the nacelle 62. Accordingly, the three gas inlets address the gas product to the compressor wheel 40 in the optimum angle of attack for which the wheel impellers are designed. In this regard, straightening vanes 98 supported by ribs 94 extending radially inwardly of housing 36, cooperate to properly orient the gas flow from the turbine nozzle 92 and turbine wheel 60 for admittance to the compressor wheel 40.

Our compressor 10 is especially arranged to facilitate maintenance, the two compressing stages 16 and 18, the valve 80, and the inter-cooler 22 and the demisters 26 and 26' being readily accessible and replaceable. Housings 36 and 46 are easily removable from the front of the casing 30, following the removal of the securing hardware. With the housings 36 and 46 removed, the compressor wheels 40 and 48 are slidably removable, with their associated enclosures, from the gear train 56 engaged therewith. The compressor wheel 40 and turbine wheel 60 are replaceable as a unit, the two being integral with a common shaft.

With reference to FIG. 3, coolant supply such as water is admitted to the cooler 22 by means of an inlet pipe and discharged by pipe 112. A throttle valve 114 is arranged in pipe 110 to regulate the volume of coolant admitted into the cooler. A temperature sensor 116 is coupled to the gas inlet of the cooler, for monitoring the gas inlet temperature and accordingly, is coupled to valve 114 for regulating the coolant admittance. This arrangement is provided to insure that, whatever temperature excusions the gas may describe, on admittance to the cooler, the operation of the cooler will be regulated to insure discharge of cooled gas at a fixed, optimum temperature which may be expressed as N degrees Fahrenheit. A particular compressor of our design, in accord with the invention,

comprises a cooler 22 which maintains a fixed temperato be realized from the otherwise excessively high discharge temperature of two stages.

Compressors, including recovery compressors such as the presently disclosed one of our design, are often required to ingest air at near-or below-freezing temperatures. Now, we have discovered that admixture of a third stage compressed gas product with below-freezing ambient air, in a recovery turbine, prior to admittance of the admixture to the first stage, will give rise to an icing condition.

Customarily, in fact, the mixed temperature for a three-stage unit, with recovery taken from the third stage, drops below the freezing temperature at an ambient temperature of about50 F. and below. In that the cooler 22 maintains a 95 F. air temperature, no moisture is removed from the air by the demisters 26 and 26 at those low compressor inlet temperatures. If the ambient air is saturated andthe compressor inlet temperature is below 32, the possibility of free moisture in the air is present, and therefore icing at the compressor inlet can take place.

For example, assuming an ambient air at 40 F. and 14.4 psia, the air can hold 37 grains of H 0 per pound of dry air. The three-stage compressor admixture inlet temperature for a 40 F. ambient temperature is about 29 F., as shown in the graphic chart of FIG. 7. At this temperature the air can hold only about 25 grains of H 0 per pound of dry air. The difference of 12 grains is free moisture which will eventually be converted into ice. In our second stage recovery, however, the admixture inlet temperature, for 40 F. ambient conditions, is in the order of 82 F.

As can be seen from the above discussion, the superiority of our two-stage recovery arrangement, compared to the three-stage unit, is evident. In summary, our twostage arrangement can negotiate a large inlet air temperature variation whereby the three-stage unit is limited due to probable icing conditions at the compressor inlet.

The graphic charting, of FIG. 7, illustrates only by way of example, a comparison between two-stage and three-stage recovery where some 80 percent of the machine s compressed gas product is recovered by the turbine 60 percent being delivered to end item 52. Our compressor design contemplates the maintenance of gas temperature, by cooler 22, as noted earlier, at a fixed temperature of N F.; specifically, the design figure is 95 F. The machine of this design further contemplates a second stage operative to elevate this fixed temperature to one of approximately N X, let us say, and a turbine operative to expand gas, at this temperature, to reduce the temperature thereof to one of approximately N X/n" our design figures develop N X as approximately 340F. and "N X/n as approximately F. Typically, comparable figures for threestage recovery would prescribe an outlet temperature, N X, of about 250 F and an expanded temperature of some 20 F. Now of course, these figures are arbitrary, and it is wholly within the ken and ability of those skilled in this art to effect variations thereof. For this reason, as our design is not limited to fixed second stage outlet and turbine outlet temperatures, we present our parameters symbolically, to wit: N, N X, and N X/n. However, it is unmistakably our teaching to hold cooler 22 at the predetermined N temperature F., in a preferred embodiment), to have efficient compression in a second stage which concurrently raises the gas temperature to N X (the approx. 340 F.) and to have efficient expansion in a turbine which concurrently drops the gas temperature to N X/n (the approx. 90 F.). We intend to be limited, in our inventive teaching, to no specific temperature values, yet it is to be understood that our teaching comprises the avoidance of third-stage recovery, where the thirdstage outlet gas temperature is considerably less than a second-stage outlet, and its turbine expansion temperature is but a fraction of the turbine expansion temperature of a second-stage outlet product, thereby to provide means for preventing icing of the first-stage from any moisture borne by gas admitted thereto.

While, we have described our invention in connection with a specific embodiment thereof it is to be clearly understood that this is done only by way of example and not as a limitation to the scope of our invention as set forth in the objects thereof and in the accompanying claims.

We claim:

1. A gas compressor, comprising:

at least a first gas compressing stage having means for compressing gas admitted to said stage;

first gas inlet means for admitting gas to said compressing means of said first stage;

means in fluid communication with said first stage for discharging compressed gas therefrom; gas expander means coupled to said compressing means of said first stage;

second gas inlet means for admitting gas to said gas expander means; and means for conducting expanded gas from said expander means to said compressing means; wherein one of said first and second gas inlet means is at least partially confined within the other thereof; further including a housing;

said housing having a recess formed therein; wherein said compressing and said expander means are slidably mounted in said recess; and

at least one of said gas inlet means comprises means replaceably coupled to said housing retaining said compressing and said expander means in said recess.

2. A gas compressor, according to claim 1, wherein:

said second gas inlet means includes a chamber;

said chamber having wall means therewithin subdividing said chamber; and

conduit means for admitting gas, independently, to

each subdivision of said chamber; wherein each of said subdivisions opens onto a common, an nular exit aperture upstream of said expander means.

3. A gas compressor, according to claim 2, wherein:

said conduit means comprises means supporting said chamber within said first gas inlet means. 4. A gas compressor, according to claim 2, wherein:

said conduit means comprises a first pair of conduits for admitting gas into only one subdivision of said chamber, and a second pair of conduits for admitting gas into only another subdivision of said chamber.

5. A gas compressor, according to claim 2, wherein:

said exit aperture defines an annular, constricted nozzle. 6. A gas compressor, according to claim 5, wherein:

said gas expander means is interpositioned between said first compressing stage and said nozzle. 7. A gas compressor, according to claim 5, wherein:

said nozzle comprises a turbine nozzle. 8. A gas compressor, according to claim 1, wherein:

said gas expander means comprises a turbine wheel.

9. A gas compressor, according to claim 8, wherein:

said compressing means comprises a compressor wheel rotatably mounted downstream of said turbine wheel, and said turbine wheel and said compressor wheel comprise an inseparable, integral unit.

10. A gas compressor, according to claim 1, wherein:

said discharging means comprises pathways formed in said housing for the conduct of compressed gas therethrough from said first compressing means.

11. A gas compressor, according to claim 2, wherein:

said second gas inlet means includes a substantially hollow nacelle or pod within which said chamber is defined.

12. A gas compressor, comprising:

at least a first gas compressing stage having means for compressing gas admitted to said stage;

first gas inlet means for admitting gas to said compressing means of said first stage;

means for. discharging compressed gas'from said first stage;

gas expander means coupled to said compressing ing gas admitted'to said stage;

first gas inlet means for admitting gas to said compressing means of said stage; means for discharging compressed gas from said stage; gas expander means coupled to said compressing means; I second gas inlet means expander means; and a housing; wherein said gas discharging means comprises pathways formed in said housing for the conduct of compressed gas therethrough; one of said first and second gas inlet means includes a substantially hollow nacelle or pod, and conduit means for admitting gas into said nacelle or pod; said conduit means comprising means supporting said nacelle or pod within the other of said first and second gas inlet means; and further including valve means having at least one inlet port and a plurality of outlet ports, and a valving element selectively movable to a plurality of operative positions for obstructing a conduct of gas therethrough from said inlet port to said outlet ports in a first operative position, for permitting a conduct of up to a given quantity of gas therethrough from said one inlet port to one outlet port of said plurality thereof in a second operative position, and for permitting a conduct of a progressively variable quantity of gas greater than said given quantity therethrough from said one inlet port to both said one outlet port and another outlet port of said plurality thereof in a third operative position; wherein said pathways comprise a first pathway throughconnecting said another outlet port independently with said one gas inlet means. 14. A gas compressor, according to claim 13, further including:

pressure-sending, valve-actuating means operatively throughconnected with said gas discharging means is for sensing gas pressure within said gas discharging'means. 15. A gas compressor, according to claim 14, wherein:

said pressure-sensing, valve-actuating means operatively coupled to said valving element for effecting movement thereof to dispose said valving element, gradually and automatically, in said first, second and third operative positions upon sensing given first, second and third levels of gas pressure, respectively, in said gas discharging means. 16. A gas compressor, according to claim 13, wherein:

said expander means comprises means for recovering energy from gas admitted thereto. 17. A gas compressor, according to claim 13, wherein:

for admitting gas to said gas said expander means comprises a turbine wheel, said compressing means comprises a compressor wheel, and said wheels are integrally joined together so that energy recovered by said turbine wheel via gas admitted thereto, imparts driving torque to said compressor wheel.

18. A gas compressor, comprising:

a first gas compressing stage having means for compressing gas admitted to said first stage;

first gas inlet means for admitting gas to said compressing means of said first stage;

said latter, gas admitting means comprises means supporting said chamber within the other of said first and second gas inlet means; further including at least a second gas compressing stage having means for compressing gas admitted to said second stage;

third gas inlet means for admitting gas to said compressing means of said second stage; and

means for discharging compressed gas from said second stage; wherein said latter gas admitting means for said chamber and said second stage gas discharging means are coupled, for effecting a conduct of compressed gas from said second stage into said chamber.

19. A gas compressor, according to claim 18,

wherein:

said chamber-defining means comprises a pod or nacelle; and further including a housing;

said housing having a recess formed therein; and

wherein said supporting means supports said pod or nacelle within said recess.v

20. A gas compressor, according to claim 19,

wherein:

said pod or nacelle has wall means therewithin subdividing said chamber; and I said supporting means includes conduits for admitting gas, independently, to each subdivision of said chamber.

21. A gas compressor, according to claim 19,

wherein:

said first gas inlet means comprises a tubular inlet housing;

said gas expander means and said first compressing means are slidably replaceably confined in said recess; and

said tubular inlet housing retains said gas expander means and said first compressing means in said recess.

'22. A gas compressor, according to claim 19,

wherein:

said second gas inlet means comprises passageways formed in said housing, and a plurality of annular chambers which envelop said first gas inlet means;

said supporting means includes conduits for admitting gas from said annular chambers into said pod or nacelle-defined chamber; and

said passageways openonto said annular chambers.

23. A gas compressor, according to claim 22,

wherein:

said first gas inlet means comprises a tubular inlet housing replaceably secured in said recess; and

said tubular inlet housing has a plurality of relieved areas formed in the outer surfaces thereof which, together with said recess, define said annular chamber.

24. A gas compressor, according to claim 22,

wherein:

said conduits comprise at least two pairs of conduits;

said pod or nacelle-defined chamber has wall means therewithin subdividing said chamber; and

a first pair of said conduits communicates one of said annularchambers only with one subdivision of said chamber; and

a second pair of said conduits communicates another of said annular chambers only with another subdivision of said chamber.

P0465) UNITED STATES PATENT OFFICE 1 CERTIFICATE OF CQRRECTION Patent No. 3,826,594 Dated 30 July 1974 inventor) Hanns Hornschuch, et a1.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown ,below:

Column 8, olaim 14, line 3, "pressure-sending" should read -pressuresensing.

Signed and sealed this 26th day of Novexhber 1974.

(SEAL) V Attes t;

mecoy r M. GIBSON JR.

C. MARSHALL DANN Attesting Officer Commissioner of Patents 

1. A gas compressor, comprising: at least a first gas compressing stage having means for compressing gas admitted to said stage; first gas inlet means for admitting gas to said compressing means of said first stage; means in fluid communication with said first stage for discharging compressed gas therefrom; gas expander means coupled to said compressing means of said first stage; second gas inlet means for admitting gas to said gas expander means; and means for conducting expanded gas from said expander means to said compressing means; wherein one of said first and second gas inlet means is at least partially confined within the other thereof; further including a housing; said housing having a recess formed therein; wherein said compressing and said expander means are slidably mounted in said recess; and at least one of said gas inlet means comprises means replaceably coupled to said housing retaining said compressing and said expander means in said recess.
 2. A gas compressor, according to claim 1, wherein: said second gas inlet means includes a chamber; said chamber having wall means therewithin subdividing said chamber; and conduit means for admitting gas, independently, to each subdivision of said chamber; wherein each of said subdivisions opens onto a common, annular exit aperture upstream of said expander means.
 3. A gas compressor, according to claim 2, wherein: said conduit means comprises means supporting said chamber within said first gas inlet means.
 4. A gas compressor, according to claim 2, wherein: said conduit means comprises a first pair of conduits for admitting gas into only one subdivision of said chamber, and a second pair of conduits for admitting gas into only another subdivision of said chamber.
 5. A gas compressor, according to claim 2, wherein: said exit aperture defines an annular, constricted nozzle.
 6. A gas compressor, according to claim 5, wherein: said gas expander means is interpositioned between said first compressing stage and said nozzle.
 7. A gas compressor, according to claim 5, wherein: said nozzle comprises a turbine nozzle.
 8. A gas compressor, according to claim 1, wherein: said gas expander means comprises a turbine wheel.
 9. A gas compressor, according to claim 8, wherein: said compressing means comprises a compressor wheel rotatably mounted downstream of said turbine wheel, and said turbine wheel and said compressor wheel comprise an inseparable, integral unit.
 10. A gas compressor, according to claim 1, wherein: said discharging means comprises pathways formed in said housing for the conduct of compressed gas therethrough from said first compressing means.
 11. A gas compressor, according to claim 2, wherein: said second gas inlet means includes a substantially hollow nacelle or pod within which said chamber is defined.
 12. A gas compressor, comprising: at least a first gas compressing stage having means for compressing gas admitted to said stage; first gas inlet means for admitting gas to said compressing means of said first stage; means for discharging compressed gas from said first stage; gas expander means coupled to said compressing means; and second gas inlet means for admitting gas to said gas expander means; wherein one of said first and second gas inlet means includes a substantially hollow nacelle or pod, and means for admitting gas into said nacelle or pod; and said latter gas admitting means comprises means supporting said nacelle or pod within the other of said first and second gas inlet means.
 13. A gas compressor, comprising: a gas compressing stage having means for compressing gas admitted to said stage; first gas inlet means for admitting gas to said compressing means of said stage; means for discharging compressed gas from said stage; gas expander means coupled to said compressing means; second gas inlet means for admitting gas to said gas expander means; and a housing; wherein said gas discharging means comprises pathways formed in said housing for the conduct of compressed gas therethrough; one of said first and second gas inlet means includes a substantially hollow nacelle or pod, and conduit means for admitting gas into said nacelle or pod; said conduit means comprising means supporting said nacelle or pod within the other of said first and second gas inlet means; and further including valve means having at least one inlet port and a plurality of outlet ports, and a valving element selectively movable to a plurality of operative positions for obstructing a conduct of gas therethrough from said inlet port to said outlet ports in a first operative position, for permitting a conduct of up to a given quantity of gas therethrough from said one inlet port to one outlet port of said plurality thereof in a second operative position, and for permitting a conduct of a progressively variable quantity of gas greater than said given quantity therethrough from said one inlet port to both said one outlet port and another outlet port of said plurality thereof in a third operative position; wherein said pathways comprise a first pathway throughconnecting said another outlet port independently with said one gas inlet means.
 14. A gas compressor, according to claim 13, further including: pressure-sending, valve-actuating means operatively throughconnected with said gas discharging means is for sensing gas pressure within said gas discharging means.
 15. A gas compressor, according to claim 14, wherein: said pressure-sensing, valve-actuating means operatively coupled to said valving element for effecting movement thereof to dispose said valving element, gradually and automatically, in said first, second and third operative positions upon sensing given first, second and third levels of gas pressure, respectively, in said gas discharging means.
 16. A gas compressor, according to claim 13, wherein: said expander means comprises means for recovering energy from gas admitted thereto.
 17. A gas compressor, according to claim 13, wherein: said expander means comprises a turbine wheel, said compressing means comprises a compressor wheel, and said wheels are integrally joined together so that energy recovered by said turbine wheel via gas admitted thereto, imparts driving torque to said compressor wheel.
 18. A gas compressor, comprising: a first gas compressing stage having means for compressing gas admitted to said first stage; first gas inlet means for admitting gas to said compressing means of said first stage; means for discharging compressed gas from said first stage; gas expander means coupled to said compressing means; and second gas inlet means for admitting gas to said gas expander means; wherein one of said first and second gas inlet means includes means defining a substantially hollow chamber, and means for admitting gas into said chamber; and said latter, gaS admitting means comprises means supporting said chamber within the other of said first and second gas inlet means; further including at least a second gas compressing stage having means for compressing gas admitted to said second stage; third gas inlet means for admitting gas to said compressing means of said second stage; and means for discharging compressed gas from said second stage; wherein said latter gas admitting means for said chamber and said second stage gas discharging means are coupled, for effecting a conduct of compressed gas from said second stage into said chamber.
 19. A gas compressor, according to claim 18, wherein: said chamber-defining means comprises a pod or nacelle; and further including a housing; said housing having a recess formed therein; and wherein said supporting means supports said pod or nacelle within said recess.
 20. A gas compressor, according to claim 19, wherein: said pod or nacelle has wall means therewithin subdividing said chamber; and said supporting means includes conduits for admitting gas, independently, to each subdivision of said chamber.
 21. A gas compressor, according to claim 19, wherein: said first gas inlet means comprises a tubular inlet housing; said gas expander means and said first compressing means are slidably replaceably confined in said recess; and said tubular inlet housing retains said gas expander means and said first compressing means in said recess.
 22. A gas compressor, according to claim 19, wherein: said second gas inlet means comprises passageways formed in said housing, and a plurality of annular chambers which envelop said first gas inlet means; said supporting means includes conduits for admitting gas from said annular chambers into said pod or nacelle-defined chamber; and said passageways open onto said annular chambers.
 23. A gas compressor, according to claim 22, wherein: said first gas inlet means comprises a tubular inlet housing replaceably secured in said recess; and said tubular inlet housing has a plurality of relieved areas formed in the outer surfaces thereof which, together with said recess, define said annular chamber.
 24. A gas compressor, according to claim 22, wherein: said conduits comprise at least two pairs of conduits; said pod or nacelle-defined chamber has wall means therewithin subdividing said chamber; and a first pair of said conduits communicates one of said annular chambers only with one subdivision of said chamber; and a second pair of said conduits communicates another of said annular chambers only with another subdivision of said chamber. 